Evaluation of the proximate composition and enterobacteriaceae content of locally processed soyabean infant food supplements sold in Benin City, Southern Nigeria

Abstract

Weaning has been described as a period of vulnerability for the child to infection due to a high risk of exposure to food-borne pathogens. The aim of this study was to determine the proximate composition and the prevalence of Enterobacteriaceae in locally processed soyabean infant food supplements sold in Benin City, Edo State, Nigeria. One hundred and eighty samples were obtained, sorted based on formulation and assessed for evidence of product registration. The physicochemical and proximate characteristics of each sample was determined using standard methods. Routine bacteriological methods were employed for the enumeration and isolation of bacteria and isolates were identified using culture based as well as molecular techniques. Most, (70%) of the products evaluated were unbranded, while 30% were branded. Total bacterial counts ranged from 5.38 ± 1.53 to 6.21 ± 0.42 log10 cfu/g (p>0.05),
while, Enterobacteriaceae counts were 3.05 ± 0.94 to 3.68 ± 0.37 log10 cfu/g. The pH and total titratable acidity values ranged from 6.42 ± 0.20 to 6.72 ± 0.05 and 0.13 ± 0.01 to 0.24 ± 0.06 g/l respectively. The proximate composition of the samples, were in the range of 1.33 ± 0.50 to 4.71 ± 1.20% (moisture); 19.92 ± 12.90 to 45.61 ± 10.20% (crude protein); 24.19 ± 17.44 to 49.70 ± 5.16% (carbohydrate); 12.67
± 9.07 to 29.08 ± 11.20% (lipid); 2.14 ± 0.05 to 5.91 ± 2.30% (crude fibre) and 1.82 ± 1.14 to 6.38 ± 0.10% (ash). Enterobacteriaceae isolates identified in this study, were Enterobactercloacae (10.0%), Proteus mirabilis (10.0%), Enterobacter hormaechei (6.67%), Salmonellaenterica (20.0%), Klebsiella pneumoniae (23.33%), Klebsiellaoxytoca (10.0%), Klebsiella aerogenes (13.33%), Raoultella
ornithinolytica (3.33%) and Cronobacter sakazakii (3.33%).Although the products were of good nutritional quality, the prevalence of Enterobacteriaceae reported, further underscores the health hazards posed by these supplements especially to vulnerable infants.